K
Kevin Aylward
Terry said:If I was simulating it (im not) I'd bung in a resistor, and step its
value to see how much is needed to wreck the circuit. And I would
curse that I cant step a component in a logarithmic fashion, forcing
me do do multiple iterations by hand.
Not in SS
You can put lists of component values in a file and have all
combinations automatically done with one run button press.
I should add a direct log sweep mode though.
Murphy suggests that the critical winding resistance is 20% below
that of the transformer you choose
Without bothering to estimate its actual value, but if say Isat of
1mA is required then 150mV/1mA = 150 ohms, so Rwinding probably wants
to be < 50 ohms. The winding resistance varies in proportion to the
square of the number of turns (for constant winding area
utilisation), so it would be possible to design such a non-starting
transformer.
Worst case for this circuit is a bit tricky. The Idss will vary quite a
lot over device and temperature, as will the transformer saturation
point.
Kevin Aylward
[email protected]
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.